From 93e12905d88f591c6894777a8409e75118e540e8 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 14 Apr 2018 16:28:19 +0300
Subject: [PATCH] Support more ways of specifying code point ranges

---
 Readme    |  7 ++++++-
 ttf2png.c | 43 +++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/Readme b/Readme
index 3e9eb40..7ce6e70 100644
--- a/Readme
+++ b/Readme
@@ -13,7 +13,9 @@ Command-line options
 
   -r <low>,<high>
     Range of code points to convert, specified as unicode code points.  The
-    default is 0,255, matching the ISO-8859-1 (Latin-1) character set.
+    default is 0,255, matching the ISO-8859-1 (Latin-1) character set.  Code
+    points can be specified as plain numbers, unicode code points (U+xxxx) or
+    UTF-8 characters.
 
   -s <pixels>
     Font size to use.  The default is 10 pixels.
@@ -133,6 +135,9 @@ some fonts, not all of the glyphs fit completely inside the character box.
 
 Changelog
 
+next
+- Alternate ways of specifying code point ranges
+
 1.1
 - Controllable margin and padding in packed mode
 - Do not generate overly large images in sequential grid mode
diff --git a/ttf2png.c b/ttf2png.c
index d9869bf..15b554d 100644
--- a/ttf2png.c
+++ b/ttf2png.c
@@ -66,6 +66,7 @@ typedef int bool;
 void usage(void);
 int convert_numeric_option(char, int);
 void convert_code_point_range(char, unsigned *, unsigned *);
+unsigned str_to_code_point(const char *, char **);
 void convert_size(char, unsigned *, unsigned *);
 unsigned round_to_pot(unsigned);
 void *alloc_image_data(size_t, size_t);
@@ -293,11 +294,11 @@ void convert_code_point_range(char opt, unsigned *begin, unsigned *end)
 		return;
 	}
 
-	value = strtol(optarg, &ptr, 0);
+	value = str_to_code_point(optarg, &ptr);
 	if(value>0 && *ptr==',')
 	{
 		*begin = value;
-		value = strtol(ptr+1, &ptr, 0);
+		value = str_to_code_point(ptr+1, &ptr);
 		if(value>0 && !*ptr)
 		{
 			*end = value;
@@ -309,6 +310,44 @@ void convert_code_point_range(char opt, unsigned *begin, unsigned *end)
 	exit(1);
 }
 
+unsigned str_to_code_point(const char *nptr, char **endptr)
+{
+	if(nptr[0]=='U' && nptr[1]=='+')
+		return strtoul(nptr+2, endptr, 16);
+	else if(nptr[0]&0x80)
+	{
+		unsigned bytes;
+		unsigned code;
+		unsigned i;
+
+		if(endptr)
+			*endptr = (char *)nptr;
+
+		for(bytes=1; (bytes<4 && (nptr[0]&(0x80>>bytes))); ++bytes)
+			if((nptr[bytes]&0xC0)!=0x80)
+				return 0;
+		if(bytes<2)
+			return 0;
+
+		code = nptr[0]&(0x3F>>bytes);
+		for(i=1; i<bytes; ++i)
+			code = (code<<6)|(nptr[i]&0x3F);
+
+		if(endptr)
+			*endptr = (char *)nptr+bytes;
+
+		return code;
+	}
+	else if(isdigit(nptr[0]))
+		return strtoul(nptr, endptr, 0);
+	else
+	{
+		if(endptr)
+			*endptr = (char *)nptr+1;
+		return *nptr;
+	}
+}
+
 void convert_size(char opt, unsigned *width, unsigned *height)
 {
 	int value;
-- 
2.43.0